Most of the body is fawny gray with a white chest and belly. The nape and shoulders are reddish leading to the common name “red-necked wallaby.” The tail is gray on top and white below. Hands and feet are gray with darker fur at the ends of the digits. The muzzle is dark brown and the ears are long.

One offspring is born at a time after a gestation period of 30 days and weigh less than 1 gram (.04 oz) at birth. The mother prepares a path from the birth canal to the pouch by licking her fur so the fur lies flat and in the direction the joey must travel; the moisture keeps the joey from drying out before reaching the pouch. The journey from birth canal to pouch takes 3-5 minutes. Once in the pouch, the joey latches onto a nipple that expands in the joey mouth to ensure continual nourishment of milk from the mother during the remaining development of the joey. The newborn’s eyes open between 135 and 150 days after birth (4-4.5 months), and fur begins to develop after about 165 days (4.5-5.5 months). A joey will first begin to look out of the pouch at 6 months and will emerge at 7 months. It will move in and out of its mother’s pouch to nurse for about 280 days (9 months) and continue to suckle for 12-17 months. Another offspring, resulting from a post-partum mating, can be born just 16 to 29 days after the previous joey emerges from the pouch. On the mainland, offspring can be born in any month although most are born during the summer (December – February). On the island of Tasmania, births occur only between late January and July with most young born in February or March. Male are sexually mature at 608 days (1.5 yrs) and females as early as 11 months.

The King Island wallaby belongs to a family of marsupial mammals that includes wallabies, kangaroos, and their relatives. Most members of this group have long, narrow hind feet, powerful hind limbs, and long, heavy tails which they use for bipedal hopping. There are two subspecies of Macropus rufogriseus:M. rufogriseus banksianus inhabits the Australian mainland while the subspecies M. rufogriseus rufogriseus is found throughout Tasmania and the Bass Strait islands. King Island is one of two large islands located in the Bass Strait between the island of Tasmania and the southeastern coast of Australia. Bennett’s wallaby is another common name for the island subspecies.

Bennett’s wallabies are solitary, although they may forage in groups of up to 30 individuals. They use their tails as props. They spend daylight hours under cover, and they cool themselves by licking their hands and forearms.

One reason wallabies and kangaroos are so successful is that they have evolved stomachs with many chambers. Some of these chambers hold microorganisms that ferment the rough vegetation and make it more nutritious (much as a cow’s stomach does). Wallaby teeth get worn down chewing the tough plants but worn-out teeth are replaced by less used ones that move towards the front of the mouth.

At the present time, M. rufogriseus is listed by the IUCN as a species of Least Concern because it has a relatively wide distribution, tolerates a broad range of habitats, has a large population (particularly on Tasmania), and lacks major threats. This species is protected by law in all states where it occurs.